wireframe

a.k.a. wire frame, page schematic, screen blueprint

A website "wireframe" is a visual guide that represents the skeletal framework of a website. The wireframe depicts the page layout or arrangement of the website’s content, including interface elements and navigational systems, and how they work together. The wireframe usually lacks typographic style, color, or graphics, since the main focus lies in functionality, behavior, and priority of content. In other words, it focuses on “what a screen does, not what it looks like.”